About Carychium tridentatum (Risso, 1826)
The scientific name of this species is Carychium tridentatum (Risso, 1826). Its shell measures 1.8-2.3 mm in height and 0.8-0.9 mm in width. This species has a more slender shell than Carychium minimum. When opening the last whorl above the aperture, the parietalis – a spiral ridge on the parietal region that projects into the interior of the shell – can be seen descending in a characteristic double curve. This species occurs in European countries and islands, the Mediterranean, the Caucasus region, and North Africa. Records of Carychium striolatum J.R. Bourguignat, 1857, a synonym of this species, come from Siberia. Documented European countries and territories where it occurs include: Belgium, Bulgaria, Czech Republic, Netherlands, Poland, Slovakia, Great Britain, Ireland, Ukraine, Albania, Andorra, Austria, Azores, Belarus, Bulgaria, Channel Islands, Croatia, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Italy, Kaliningrad, Latvia, Liechtenstein, Lithuania, Luxembourg, Madeira, Moldova, Montenegro, Norway, Romania, Serbia, Slovenia, Spain, Sweden, and Switzerland. It has been introduced to North America, specifically to British Columbia, Canada.
